> For the complete documentation index, see [llms.txt](https://zhenchaogan.gitbook.io/leetcode-solution/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://zhenchaogan.gitbook.io/leetcode-solution/leetcode-1784-check-if-binary-string-has-at-most-one-segment-of-ones.md).

# LeetCode 1784. Check if Binary String Has at Most One Segment of Ones

Given a binary string `s` **​​​​​without leading zeros**, return `true`​​​ *if* `s` *contains **at most one contiguous segment of ones***. Otherwise, return `false`.

**Example 1:**

```
Input: s = "1001"
Output: false
Explanation: The ones do not form a contiguous segment.
```

**Example 2:**

```
Input: s = "110"
Output: true
```

**Constraints:**

* `1 <= s.length <= 100`
* `s[i]`​​​​ is either `'0'` or `'1'`.
* `s[0]` is `'1'`.

## Solution:

```
class Solution {
public:
    bool checkOnesSegment(string s) {
        return s.find("01") == string::npos;
    }
};
```